JPH01294406A - Packaging machine - Google Patents

Abstract

PURPOSE: To give tension to a wrapping material to conduct wrapping by transporting the wrapping material to an article so as to make the material tense around the article. CONSTITUTION: An upper sliding surface 149 is provided near a band 148, friction between a lower portion of a wrapping material 136 and a surface 153 tends to pull the wrapping material around the packet, while an upper rear portion 136A of the wrapping material 136 is held with respect to the back of a packet 101 by a pusher 150, and makes close wrapping with the wrapping material around the packet. The surface 153 and a lower surface of the band 148 have contact with the wrapping material 136 when carried by a pusher 154, similarly to transportation of the packet with the pusher 150, and maintain control and tension of the wrapping material 136. A member 180, namely a surface 157, and a front 153 maintain wrapping tension until sealing finishes during transport of the packet 101 by a pusher 158.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates in particular to a packaging machine for wrapping packets of cigarettes with transparent plastic films.

Means and Operations for Solving the Problems According to one aspect of the present invention, a packaging machine includes a device for transporting (11) a spaced series of articles along a path, and a device for transporting (11) a series of spaced apart articles to said articles. a device for dispensing, a device for positioning the first portion of the packaging material with respect to an article moving on the path, and a device for tensioning or tautening the packaging material about at least a portion of the article. and apparatus for moving or attempting to move the second portion of packaging material relative to the article. In a preferred arrangement, the articles are packets and are referred to as such below for convenience. Preferably, the placement device is part of the device for transporting the bucket along the path and can conveniently be provided with a pusher body that engages the rear side of the partially wrapped packet. The pushing body also serves to fold the first portion of the packaging material towards the rear side. The device for moving or attempting to move has a surface for relatively moving the second portion of the packaging material, and the FJI between the packaging material and the surface is
! I is sufficient to create a drag force that causes the packaging material to tighten or tend to tighten around the packet.

The surface may be stationary or moving, for example a portion of packaging material may be in contact with a conveyor moving at a speed different from that of the packets. The abrasion between the surface and the packaging material is preferably relatively low, so that there is no risk of marking or otherwise damaging the packaging material. There can be more than one surface. For example, a packet with enveloping packaging material can pass between upper and lower surfaces, each of which tends to tension the packaging material around the packet. It is possible to apply light pressure between the surface and the packet to increase the effect of drag on the packaging material.

The use of sliders or other surfaces to ensure the tension of the packaging material is particularly valuable during the initial wrapping of the packaging material around the packet. For this purpose, the positioning device can be a first folding pusher. However, maintaining the tension of the packaging material is important up to the point where the packaging material is finally sealed.

Therefore, the greatest benefit from the present invention is obtained by using devices such as one or more slider surfaces up to or during the sealing of at least the first seam of the packaging material. If the packaging material is comprised of a thermoplastic material and the overlapping seam of the packaging material is to be sealed by heat, the seam is sealed overcoming the slight resistance to movement generated by one or more surfaces as described above. It would be preferable to convey the packet by means of a contacting heated pusher. An additional benefit obtained in this case is that the low friction ensures good contact between the pusher body and the seam, thereby promoting heat transfer.

According to another aspect of the invention, a continuous packaging machine includes at least one pusher for advancing the partially wrapped packets along a substantially straight path, the pusher including a pusher for advancing the partially wrapped packets along a substantially straight path. It includes a device for sealing the polymerized portions of the packaging material during transportation by means of a pusher and the transfer of heat between the portions. sticker .

can be carried out by heating (eg of a thermoset or thermoplastic material, which can be the packaging material itself or an attached adhesive). In this case, the pusher body preferably has an electrically heated element and cooperates with a device for controlling the current flow to the element and for maintaining an acceptable temperature range for the packet and the packaging material. It will be appreciated that in the case of thermoplastic materials, the sealing process is similar to welding, with the sealed portion being hardened by subsequent cooling of the material.

- This cooling occurs rapidly at ambient temperature due to the small amount of heat that needs to be added into the shell. In principle, a cooling press can be used, for example, to rapidly harden preheated thermoplastic adhesives that are applied to packaging materials.

According to another aspect of the invention, a packaging machine includes a device for sequentially moving a series of spaced apart packets along a path, and a machine for moving a series of spaced apart packets in a timed relationship with said packets. a device for delivering across a path whereby each packaging material is taken up by the packet, said moving device having an opposing conveyor substantially immediately downstream of the location at which the packets take up the packaging material; Each partially wrapped packet is engaged by the conveyor onto an opposing surface. Therefore, said opposing conveyors preferably engage each partially wrapped packet at about the same time. In contrast to prior art systems where such opposing conveyors (if present anyway) are well spaced from the location where the packaging material is taken away by the packet, the present configuration As soon as possible after that, maintain control of the packaging material and contact it with a surface having a speed related to the speed of the packet. This is particularly advantageous on high speed machines (eg machines capable of processing more than 400 packets per minute).

According to another aspect, the present invention provides a substantially straight path along which the packets are successively moved, and a succession of packaging materials such that each packaging material is taken up by the packets moving on the path. an apparatus for folding and sealing packaging material around the packet, the apparatus comprising: a first pushing body for moving the packet along said path; and a second pushing body for moving the packet along said path. a pusher, the second pusher is configured to take over transport of the packet on the two previous paths from the first pusher, and the second pusher is configured to A packaging machine is provided in which the bodies have complementary shapes to bring each into simultaneous and/or extended contact with different parts of the packet. 1st and 2nd
The pushing bodies preferably have a constant speed, the speed of the second pushing body being no slower than the speed of the first pushing body. At least one of the pushing bodies is capable of performing a folding action on the packaging material, so that the extended contact with the packet can be at least partially through the folded portion of the packaging material and thereby The contact can help hold the folded portion in place relative to the packet. At least one of the pushing bodies attempts to transfer heat to (or from) the overlapping seam of the packaging material so as to seal the seam and at least partially complete the seal around the packet of packaging material. It can consist of elements.

According to a further aspect of the invention, successive article conveyors having a common path section in an article packaging machine are driven by independent drives, such that the control of at least one of said drives causes the phasing of said conveyors. and/or the speed can be varied, in particular the position whereby articles are transferred between said conveyors.

In this way, the period during which the articles are contacted by the conveyor can be controlled. For example, if the machine is of variable speed and one conveyor carries a heated pusher for applying heat to the packaging material to seal its overlap, control of the drive may be substantially The duration can be controlled so that a constant amount of heat is transferred regardless of the speed of the machine.

Some or all of the various aspects of the invention may be incorporated into a packaging machine in any combination.

Although the packaging machine has been described with particular reference to packets, the invention is applicable in all respects to machines for packaging or bagging other articles, both within and outside the cigarette industry, and is described herein. References to "packet" and "packaging material" and "packaging" should be construed accordingly. For example, the invention can be used in cigarette bundle packaging (ie, packs), ie, in cigarette machines, or it can be used in soap bars.

The invention will be further described, by way of example only, with reference to the accompanying schematic drawings, in which: FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a machine for wrapping packets of cigarettes in transparent films of thermoplastic material.

The machine includes a film reel unit 10 with carriers for two film reels 12,14. A splicer unit 16 is provided for joining the trailing end of the film from the in-use reel 12 to the leading end of the replacement reel 14 (and vice versa).

Filmware 18 passes from film reel unit 1o around several idlers and tension rolls to feeding and cutting unit 20. Immediately upstream of unit 2o, tear tape 22 is delivered onto film web 18 from tear tape reel 24. Tear tape 22 passes through a hot wax applicator 26 before being delivered to filmware 18. The unit 20 includes a roll 28 and a counter roll 80, which rolls together tear tape 2
2 onto the film 18, thereby holding them together by hot wax. Roll 28 includes a narrow cutter 31 for cutting tear tape 22 and underlying film 18 to create tear tabs into the finished packaging material.

The feeding and cutting unit 20 includes a pair of feeding rolls 32 located below the rolls 28,29.

Roll 32 includes film web 18 and tear tape 2
2 controls the speed with which each reel 12.24 is withdrawn. Immediately below the roll 32, the film web 18 (and attached tears) is deposited to form the packaging material 36.
There is a rotary cutter 30 for cutting continuous image portions of the tape 22). The cutter 30 cuts the film web 18
on opposite opposing surfaces or edges (not shown).

Continuous packaging material 36 is drawn along a substantially vertical path by a pair of laterally spaced feed bands 34 that cooperate with a similar pair of opposing bands (not shown). The packaging material is thereby delivered between a pair of laterally spaced bands. The packaging material 36 is fed to the band 34 at a speed slightly faster than the feeding speed of the roller 32.
, so that each wrapping material is separated from the unlit portion of the film web 18 .

Band 34 directs each wrapping material 36 into the path of the packet being conveyed along horizontally extending wrapping tube 37. The packets are received in the line 37 on the lower band 40, so that each packet has a pusher body 4 engaged on its rear side.
2. Packets are received on the band 4o from the cigarette backing machine or from an accumulator unit or handling unit located downstream of the cigarette backing machine. If we consider that each packet has two relatively large sides, two relatively narrow sides, and two ends, then the orientation of the packets is such that their faces are horizontal and their ends are on line 37. The pushing body 42 is parallel to the moving direction and the rear side of each packet is as described above.
It is adapted to be engaged by.

Upper band 38 is positioned above the upstream portion of band 40. Band 38 carries pushers 42 arranged to cooperate with pushers 42 on band 40 . Pressing body 42 and cutter 30 m time and band 34 and band 38.40
The relative velocity of each wrapping material 36 is substantially centrally engaged by the front side of the packet and between the upper and lower plates 44, 46 located just beyond the path of the wrapping material 36 between the bands 34. It is now being pushed into the

The packet is thus surrounded on its front side and on its upper and lower sides by a wrapping material 36, the free ends of the wrapping material extending parallel to the upper and lower sides of the packet. Packaging material 36
The upper free end of is engaged by a pusher 50 on the upper band 48 just beyond the plate 44. The pressing body 5o is a packaging material 36
The upper free end is folded against the rear side of the packet and the packet is conveyed further along line 37.

The downstream portion of upper band 48 overlaps the upstream portion of lower band 52, which travels faster than band 48.

The timing between pushers 52 and 54 is such that pusher 54 engages the lower free end of each wrapping material 36 and folds it upwardly against the rear side of the packet. Packaging material 36
The length of the lower free end overlaps the upper free end and holds it in place.

(by means of the pushing body 54). An upper heater band 56 carrying an electrically heated pusher body 58 has an upstream portion that overlaps the downstream portion of band 52. Band 56 travels faster than band 54 and heated pusher 58 engages the back side of each packet over the overlapping portion of wrapping material 36. During transport of the packet by the pusher 58, sufficient heat is transferred to the thermoplastic material of the overlapping portions of the packaging material to cause the portions to be sealed together.

Downstream of the heater band 56, the packets are conveyed onto a lower flat band 6o, which runs at the same speed as the heater band 56 and also pushes the packets onto a pushing body 58.
support while transporting.

The packet carried by band 60 downstream of heater band 56 has open rectangular tubular wrapping material sections extending outwardly from each end of the packet.

Each of these portions has upper and lower surface portions and front and rear portions. A rotating fold VS62 having a circumferential velocity greater than the linear velocity of the packet engages the rear portions and folds them against the ends of each packet. A stationary plow folder 63 engages the front sections and folds them against the ends of each packet, and also holds the folded back sections in position downstream of the rotating folder 62. act.

Next, another plow folder 64 folds first the lower side part of the packaging material and then the upper side part onto the already folded side parts.

Downstream of the plow folder 64, each packet passes between a pair of driven bands 66 that hold the folded end portions of the packaging material in place and also remove the folded ends from the heater 68. of heat is applied to seal the end folds of each packet and thereby complete the packaging of the packet.

The wrapped packets are delivered from the end of the band 60 to another processing device, such as a cartoning machine or a parcel machine.

2-7 show portions of a modified packaging machine. This machine is similar in many respects to the machine of FIG.

The delivery of packaging material into and along vertical path 100 is similar to the delivery of packaging material 36 in FIG.

Equally spaced pushing bodies 142 (only one of which is shown)
A lower band 140 carrying successive packets laterally extends along a supporting surface 141 and along the path 100.
so that the packet is fed across the packaging material 136
and is received between the upper run of flat band 145 and the lower run of band 148 carrying spaced pushers 150 (only one shown). band 145
and 148 extend almost to path 100, and packet 1
01 (and the packaging material 136) as it passes through the path 100.
It engages and grips immediately after traversing it. Apparently, due to the curvature of the pulley, bands 145, 148 immediately after packaging material 136 is deflected by packet 101.
contact with packaging material 136 is not possible. For this purpose, the packet 1 has a slightly curved lower leading edge and
Upper and lower guides 144, 146 defining holes only slightly larger than the height of 01 are provided and additionally ensure a good initial wrapping of the packaging material 136 around the packet. The drive pulley of band 145 may be placed directly below the small upper pulley instead of being coaxial with the upstream pulley of band 152. This allows the use of a full width pusher 154 (ie, similar to pusher 154A of FIG. 8) since the possibility of interference with band 145 is eliminated.

Bands 140, 145 and 148 have the same linear velocity. The timing of the pushers 150 is such that each one engages the upper rear portion 136A of the packaging material 136, folds it along the upper rear edge portion of the packet 101 and then folds it into the band 14.
The packaging material is held against the rear side of the packet as it is pressed along another laterally spaced support surface 153 starting downstream of the short upper run of 5. The portion 136A is pressed into the packet 1 by the pusher 150.
While being held against the rear side of 01, the packaging material 13
The W, rub between the lower portion of 6 and surface 153 acts to tend to draw the packaging material around the packet and to ensure that the packaging material is wrapped tightly around the packet.

A lower band 152 carrying spaced pushers 154 is located downstream of band 145. The linear velocity of band 152 is faster than the linear velocity of band 148. The pushers 154 are each adjusted to engage the lower rear portion 136B of the packaging material 136 and fold it upwardly over the rear side of the packet 101 and overlap the previously folded upper portion 136A. It will be time. Packet 101 is then conveyed onto surface 153 by pusher 154, which holds stacked packaging material 136 in place around the packet. The surface 153 and the lower surface of the band 148 are exposed to the pusher 150 while the packet is being transported by the pusher 150.
4, it comes into contact with the packaging material 136 and acts to maintain the υlJt[l and tension of the packaging material 136.

Overlapping the surface 153 and the downstream end of the band 152 is a heater conveyor 156 comprising laterally spaced chains or bands with spaced heating pushers 158 extending between the bands. The bands of conveyor 156 are spaced apart by more than the width of packaging material 136. Conveyor 156 has a higher linear speed than band 152 and pusher 158 is configured such that the rear side of each packet 101 is engaged by the pusher which takes over conveyance of the packets from pusher 154 on surface 153. Ru. Heating pusher 158 engages the overlapping portions of packaging material 136 and transfers sufficient heat to seal the portions together during transport of the packet. Pressing body 15
8 has a lateral extension passing between the upper and lower members, which improves the stiffness of the lower run of the conveyor 156 and acts as a guide and directs the vertical movement of the pushers during their working run. prevent.

The pushing body 158 is electrically heated and stationary! Ill S
sliding contact at their ends that engage bodies (as indicated at 159). The current to the pusher 158 is preferably within a temperature range that the pusher can tolerate (typically 120-
160° C.), which can be achieved by controlling the voltage at which the current is applied as well as the period during which the current is applied.

During transport by pusher 158 , the upper portion of packaging material 136 and packet 101 are under the control of stationary surface 157 .

The packaging material portion covering the upper surface of the packet 101 is the surface 15.
7 can be directly contacted. However, it is preferred to force the packet elastically onto the surface 153.

For this purpose, a pressing member 180, best illustrated in FIGS. 9 and 10, is attached to the underside of the surface 157 and has a light spring 182 pressing it into contact with the packets.
, whereby the packet is lightly pressed downward onto surface 153. The lower surface of the pusher members 180 (there may be four in series along the length of the working run of the pusher 158) as well as the front face 153 are of a relatively low friction material;
The slight additional FJ rub caused by pressing onto the packet ensures good contact between each pusher 158 and the packet. Member 180 (i.e. surface 157) and front surface 15
3, the packet 1 is pressed by the pressing body 158 until the sealing is completed.
01 creates a drag force that helps maintain the tautness of the package during transportation.

At its downstream end, the heater conveyor 156 overlaps with another lower conveyor 170 carrying barbed pushers 172. Conveyor 170 has a higher linear speed than conveyor 156 so that conveyance of the packets is transferred from pusher 158 to pusher 172.

Conveyors 140 (and 145 and 148) vs. 152 to 1
The speed ratio of 56:170 is approximately 1:1.20:1.33:1
．． It is 40. Therefore, the spacing between the packets (and the pushers on their respective conveyors) is in the same ratio. conveyor 1
40, 148, 152, 156 and 170 each have four equally spaced pushers.

Push bodies 150.154.158.172 so as to reduce the impact on the packet 101 and the resulting slippage of the packaging material 136 against the packet.
It may be advantageous to reduce or eliminate speed differences between one or more successive pairs of conveyors, and thus their respective conveyors. This is especially true for push bodies 150 and 15.
Valid for the first transfer between 4 and 4. In this case, the conveyors 148 and 152 should run at the same speed (
(including reducing the pitch between the pushers 154 to the pitch of the pushers 150111) between the packet 101 and the packaging material 1
36 has the additional advantage of potentially maximizing the period during which it is subjected to drag on surface 153 and therefore the benefit this has on package tension and control.

Each of the conveyors 1.40, 148, 152, 156.170 has a timing band (or belt), and the use of these provides greater compliance, unlike chains, and thus reduces the impact on the packets 101. potential aid to reduce The bands are arranged such that they directly contact the packaging material 136 and control the packaging material and the packet 101, e.g. by bands 148 and 170, and further include surfaces on which the packet slides (e.g. surface 15).
3) and the surface on which the packet is directly conveyed (eg of band 170).

Pushers 142 and 150 have a generally flat rectangular cross section as shown in FIG. The pushers 1s4.158 and 172 have complementary shapes as shown in FIGS. 4 and 5 intended to facilitate transfer and allow sufficient contact with the packet, but each of these has a complementary shape to the pusher 142. It can also have a flat rectangular shape similar to the .150.

During transfer between pushers, each packet is contacted by both pushers for a short period of time (or for a long time if speed differences are substantially eliminated).

A continuous portion of surface 153 can extend to the left as shown in FIG. .

(The conveyor 170 can preferably have a single central band instead of the laterally spaced bands shown in FIG. 6 for this purpose.) Additionally, the upper sliding surface 14
9 (which may have laterally spaced portions) may be provided in the vicinity of the band 148 such that the pusher body 150 extends below but the surface is below the lower run of the band 148. , whereby it contacts the packaging material 136 on the passing packet 101. conveyor 1
48, surface 149 and/or pusher body 150 can have laterally spaced portions to accomplish this.

Therefore, surface 149 is approximately at the same level as surface 157. A little additional friction between the portion of wrapping material 136 around the upper surface of packet 101 and the resting surface below band 148 can further aid in wrapping tension and control.

It may be preferable for the upper control surface 149 to begin at or downstream of the location where the pusher body 154 first contacts the packet 101. The surface 149 may extend beyond the downstream pulley of the band 148 to maintain control of the upper portion of the packaging material 136 as far as possible into the path of the heated pusher body 158.

With particular reference now to FIGS. 6 and 7, which show portions of the machine primarily downstream of those shown in FIG.
0 moves the packet between rotary folders 162 to form a back end fold of the packaging material. Folder 162 has upper and lower elements 161 (FIG. 7) that pass above and below, respectively, static folder 163 during rotation of folder 162 to form a front end fold. forming and retaining and retaining the rear end bend. The bender 163 is the bender 16
It has a retraction guide 163A extending between the two elements 161.

The rear curved surface of the folder 162 serves to hold the rear end fold in place until the stationary folder 163 takes over. This effect can be enhanced by displacing the folder 162 with a short belt carrying a folder or shirring block with upper and lower elements similar to element 161.

The action of the folder 162 can be assisted by an air jet, which can be stationary or carried by the folder 162 itself. A stationary plow folder 164 completes the lower and upper face end folds. The operation of the folders 162, 163 and 164 is substantially similar to the operation of the folders 62, 63 and 64 of the machine of FIG.

Downstream of the folder 164, the side plate 165 is connected to a conveyor 170.
The folded ends of the packaging material are held in place during the transfer of the packets from 166 to an opposing conveyor band 166 that contacts both end folds of each packet. band 166
is heated by a heater block 168 containing an electrically heated cartridge element so that the end turns are sealed during passage of the packet between the bands. The material of the band 166 can typically be steel or polytetrafluoroethylene-impregnated glass fiber, selected to have sufficient thermal conductivity and resistance to the effects of relatively high temperatures. be done. Heater block 16
8 is a separately heated section to allow greater control of the heat applied to band 166 (as shown in FIG. 6).
can have. One or more of the sections can be retracted and the sections or blocks 168 can be spring-loaded (as shown at 168A in FIG. 6) toward the band 166. This ensures a reasonably constant pressure between block 168 and band 166, and also between the band and the packet, and helps accommodate slight variations in back length (end-to-end). Heater block 1
68 can be replaced or supplemented by a radiant heater, such as a halogen heater. Heat can be transferred to (or exceptionally removed from) the return run of band 166 to aid in temperature control.

It will be appreciated that each of the conveyors 140, 148, 152, 156, 170 may have a backing member adjacent its working run to support the conveyor. This may occur if the conveyor directly impinges on the packets 101 being conveyed (e.g. conveyor 170 and surface 149 shown in FIG.
may be particularly useful for conveyors (148) without

In theory, the backing member does not need to be straight. For example, if the pulleys of conveyor V 148 are set higher than shown in FIG. can be displaced downwardly by a convex backing surface.

When surface 149 extends for only a portion of the length of the lower run of conveyor 148, downstream pulley 151 can be set at a slightly higher level than upstream pulley 155, and the backing member is initially 153 (i.e. at some distance downstream of pulley 155) and then slightly angled upwardly toward pulley 151, thereby above surface 149 and downstream of the lower run of conveyor 148. can guide you. Pusher body 150 preferably contacts packaging material 136 and packet 101 immediately from pulley 155 and there is no deflection of the lower run of conveyor 148 at least upstream of surface 149. One advantage of the machine is that because the timing is referenced to the back side of the packet, it does not require adjustment of the packet carrying conveyor for changes in packet width (ie, between the sides of the packet). Also, changes in packet length can be accommodated relatively easily, for example by moving laterally spaced bands apart. Packet height (i.e. between faces)
The effect on the machine of changes in can be reduced if the configuration requires static adjustments to counter movement of the parts.

Thus, with reference to FIG. 8, which is a cross-sectional view of a slightly modified configuration on a line corresponding to line ■-■ in FIG.
49) in the vertical direction to adjust its distance. The positions of conveyors 148 and 152 remain unchanged.

The height of the top of the pushing body 154A above the diameter of the downstream pulley 174 through which the conveyor 152 passes is smaller (for example, 3
Note that m). This is the surface 153 when the pushing body turns around the pulley at the end of its working run.
Decrease the acceleration of the top packet.

At least some dimensional changes are automated1.

A code indicating the size or known packet size can be found in the control microprocessor.

Alternatively, the reference packet can be monitored, e.g. by an opto-electronic sensor integrated into or in close proximity to the machine, so that the υ1111 system can, for example, monitor the reference packet by a monitor that monitors it. Following insertion into the pocket, set the appropriate dimensional adjustments on the machine. Another sensor at the monitoring location can cooperate with a corresponding sensor to ensure that the packets have the same gender after packaging. This feature can also be used with a backing machine that can serve to check that the packets produced have the same printing, etc. as the reference packet.

It will be appreciated that the relative timing of the conveyors is particularly important when conveyances of packets are transferred between conveyors.

The conveyors may be driven from a common prime mover with appropriate gearing. Alternatively, a separate electrically controlled drive may be used to maintain timing. A combination of these is used in the machines of FIGS. 2-7. conveyor 1
48° 152 and 156 rear pulley and conveyor 14
Front pulleys 0 and 145 are driven from a first common prime mover. A second common prime mover is the front pulley of conveyor 170, the back pulley of band 166, and the rotating fold 416.
Drive 2.

The advantage of having independent drives is that they can be easily adjusted by adjusting the relative phasing of the drives to change the relative position of the pusher bodies of each conveyor when the conveyors overlap at a point where a downstream conveyor takes over conveyance of the packet. It is something that can be controlled. This is much more difficult with conventional drive structures where each conveyor is connected to a common prime mover. For this reason,
For example, in the case of conveyors 156 and 170, these conveyors may be driven independently and configured to overlap to a somewhat larger extent than shown in FIG. At this time, the relative phase of the drives can be changed (during which time the II machine is idling), so that the pusher 172 takes over conveying the packet 101 earlier or later from the pusher 158. In this way, the pushing body 158 where the packet 101 is heated
The distance between III and III that is contacted by can be adjusted. this is,
Push body 158, especially if the machine can be run at variable speeds.
It may thus be possible to keep the contact period relatively constant at different machine speeds or to otherwise vary this period if desired, which is an advantageous facility. It is also possible to easily vary the relative speeds of successive conveyors with independent drives, since the spacing between the conveyor pushers is related to the conveyor speed, i.e. the pitch between packets is Since it changes depending on the transport speed,
Usually requires replacement of at least one of the conveyors.

It may be noted that a slight speed error may occur when pusher body 142 is still in contact with packet 101 and begins to move around the downstream pulley of conveyor 140. One way to overcome this problem is to control the speed of conveyor 140 so that it is slightly slower during this period, which otherwise compensates for the increased rate of packets.

Obviously, the use of a separate electronic drive for the conveyor 140 facilitates this. Another way to deal with the same problem is to provide pusher 142 with a front surface that slopes rearward from the conveyor. Another possibility is to use a so-called chipback conveyor or - simply to provide parallel belt conveyors with links between them to keep the pushers vertical. It is even possible to configure conveyor 140 to move slightly slower than conveyors 145 and 148, so that packets are As soon as the packet is gripped by 145 and 148, it moves away from pusher 142. The question is whether speed regulation or relative control can be achieved by minimizing the height of the pusher above the effective diameter of the downstream pulley as explained with respect to FIG. S2 can be reduced without relying on a complicated push body structure.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the packaging machine, FIG. 2 is a side view of parts of the packaging machine that have been modified, and FIGS. 6 is a plan view of another part of the machine of FIG. 2, FIG. 7 is a partial sectional view along the line Vl--Vl of FIG. 6, and FIG. is a cross-sectional view of the modified machine on the line corresponding to the line ■-■ in FIG. 2, FIG. 9 is a detailed cross-sectional view on the line II-IX of FIG. 2, and FIG. It is a view in the direction of arrow X in the figure. 36.136...Packaging material, 48.52.60.66.140,145°148.1
52...Band, 50.54.58,142,150.154...Press body, 56...Heater band, 62.63.64,162,163,164...Bending device, 68: ... Heater, 100 ... Route, 101 ... Packet, 141.153 ... Surface, 144.146 ... Guide, 156 ... Heater conveyor, 157 ... Stationary surface, 158 ... Heating press body. 166... Conveyor band, 168... Heater block, 170... Conveyor, 174... Downstream pulley, 180... Pressing member, 182... Spring.

Claims (16)

[Claims] (1) a device for conveying a spaced series of articles along a path; and a device for delivering a column of packaging material to the articles; Apparatus for placing the first part of (50
, 54, 58, 150, 154, 158) and moving or moving a second portion of the packaging material relative to the article so as to tension or attempt to tension the packaging material about at least a portion of the article. A device for trying to
48, 148, 149, 153, 157, 180). (2) Placement device (50, 54, 58, 150, 154,
158) forming part of the device for conveying articles along the path. (3) The placement device is a pusher (50, 54, 58, 150, 1
54, 158). (4) The positioning device includes a device (50, 54, 150, 154) for wrapping a portion of packaging material around the article. packaging machine. 5. A packaging machine as claimed in claim 4, wherein the placement device (50, 54, 150, 154) wraps the first portion of packaging material around the article. (6) a transfer device (58, 1
58) A packaging machine according to any one of claims 1 to 5. (7) The device for moving or attempting to move the packaging material is located on at least one surface (48, 148, 149, 15).
3), wherein a second portion of packaging material is moved during movement of the article along said path, whereby friction between said surface and said second portion is applied to said second portion; A packaging machine according to any one of claims 1 to 6, which generates a drag force. (8) a stationary surface (1), the surface extending in the direction of the path;
49, 153, 157, 180). 9. A packaging machine as claimed in claim 7 or 8, characterized in that said surface comprises a surface (48, 148) moving generally in the direction of said path at a speed different from the speed of the article. (10) comprising at least two of said surfaces;
48, 149, 153, 157, 180) are spaced apart such that articles on said path pass between them and different parts of the packaging material can be contacted by said surface substantially simultaneously. A packaging machine according to any one of claims 7 to 9. (11) an elastic device (182) for applying pressure between the surface (180) and the article to increase drag on the second portion; The packaging machine described in section. (12) a support surface (153) and a movable plate (180) between which an article can move along the path; 12. A packaging according to claim 11, comprising an elastic device (182) for pressing into contact with a part of the packaged article, thereby pushing the article lightly between said movable plate and said support surface. Machine. (13) at least one pusher for advancing a partially wrapped article along said path, said pusher moving an overlapping portion of packaging material between said pusher and said pusher during transportation of said article; 13. A packaging machine according to any one of claims 1 to 12, including a device for sealing by heat transfer between the packaging machine and the packaging machine. (14) A first pusher (50, 54, 150, 154, 158) that moves the article along the route, and a second pusher (54, 58, 158) that moves the article along the route.
54, 158, 172), wherein the second pusher is configured to take over conveyance of the article on the path from the first pusher. A packaging machine according to any one of the above. (15) The first and second pushing bodies (154, 158, 1
72) each have a complementary shape so that they can contact different parts of the article simultaneously
The packaging machine described in section. (16) Continuous conveyors (48, 52, 56, 60, 148, 152) for conveying articles along said path.
, 156, 170), an independent drive for each of said conveyors, and said drives such that the phase and/or speed of said conveyor can be varied so that the position of transferring articles between said conveyors can be varied. and a device for controlling at least one of the devices.
The packaging machine according to any one of paragraphs 1 to 15.